eXogenous Kalman Filter (XKF) Non Linear Observer (NLO)
AHRS/INS + Computer - use IMUs without GNSS
SLAM
Standard Precision uBlox M9 - 50 Hz, upto 105 degree C NEO-M9L
u‑blox’s 3D ADR GNSS chip, the UBX‑M8030‑Kx‑DR - GNSS + Vehicle Data 3D ADR - ADR + elevation
UDR (Untethered Dead Reckoning) ADR (Automotive Dead Reckoning) - UDR + Wheel Tick sensor High Precision ZED-F9K - decimeter postition, RTK, 30 Hz
ZED F9K - GNSS + IMU (Dead Reckoning) - Automotive Grade ZED F9R - GNSS + IMU - Professional Grade ZED F9P - GNSS (RTK only) - Standard Grade
Radio Technical Commission for Maritime Services (RTCM) - DGNSS RTK uses RTCM protocol mostly - proprietary also exist NTRIP stands for network transport of RTCM via internet protocol Emlid NTRIP Caster for RTK
Survey of India launches CORS network (2020)
- Passive GNSS Antenna - add LNA (Low Noise Amplifier)
- High RF Interference - add SAW Filter
- SAW Filter in GPS - SMD that filters only a specific band (e.g. L1), filtering may weaken signal sometimes SAW Filter notes
Consant poor GNSS - limited dead reckoning limited poor GNSS - ok